This invention relates to take up assemblies and mechanisms for supporting lengths of various types of cable, and more particularly to a cable management system which allows a length of cable to be wound thereonto or wound therefrom without causing continuous twisting of a fixed length of cable coupling the system to an external device.
Various devices and methods have been employed for supporting a length of cable in a manner which allows the cable to be wound thereon or unwound therefrom such that the cable can be extended from, or retracted on, the apparatus. One specific application where such devices are needed is with the winding and playing of electrical or fiber optic cables. Often such cables need to be extended to a remote location which is some distance from the location where the apparatus is positioned, while still maintaining a connection of the apparatus via a fixed length of cable to an external device located at the first location. The use of the fixed length of cable allows communication signals or power signals, or other forms of data or information, to be transmitted from the external device along the fixed cable to the main cable of the system or apparatus.
As will be appreciated, a problem arises as the cable supported by the apparatus, which is typically rolled up onto a drum or other like component, is wound or unwound therefrom. A fixed length of cable attached to the drum needs to be able to rotate about its longitudinal axis to prevent the fixed length of cable from continuously twisting as the main cable is wound onto or unwound from the drum or other like component. Without some means for preventing continuous twisting of the fixed length of cable, the fixed length of cable must be periodically detached, allowed to untwist, and then reattached, to the external device as the drum or other like component holding the main length of cable is rotated.
Accordingly, there is a need for a cable management system which allows a main length of cable to be wound thereon or let out therefrom without causing continuous twisting of a fixed length of cable coupling the system to an external fixed device which is supplying power, electrical signals, optical signals or other information to the main cable.
The present invention is directed to a cable management system and method which enables a main length of cable to be wound thereon or let out therefrom without causing continuous twisting of a fixed length of cable coupled between the apparatus and a fixed, external device which supplies signals through the fixed length of cable. The system generally includes a pair of spools arranged non-parallel to one another upon which a main length of cable is supported. A fixed length of cable extending from the spools is coupled to an external device which supplies power, electrical signals, optical signals or any other form of data or information to the main length of cable supported on the spools. A member coupled to the spools supports the spools in free space.
The member is used during a cable winding or cable let out process to move the spools in a figure eight path in free space. More specifically, a first one of the spools is moved orbitally about a first axis for approximately one 360 degree revolution and then the member reorientates the system such that a second one of the spools is oriented for orbital movement about a second axis of rotation which is parallel to the first axis of rotation. The second spool is rotated for approximately one 360 degree revolution about the second axis. The member causes an alternating re-orientation of the spools such that the spools are alternately rotated about their respective axes of rotation for one 360xc2x0 revolution during the cable winding or cable let out process. As mentioned above, this causes the spools to effectively move in a figure eight path in free space during a winding or let out process.
In one preferred embodiment the spools are arranged at approximately a 45 degree angle relative to one another. In this embodiment the member which is used for rotating the spools is fixedly attached to the spools and extends from a connection point inbetween the two spools. The member is moved in the above-described figure eight pattern in free space to effect the winding or let out of the main length of cable to/from the spools.
In one preferred form a robot is used to move the member in the above-described figure eight path. In another embodiment a sphere having a figure eight track and an element disposed for movement in the figure eight track is used to control movement of the member supporting the spools.
It is a principal advantage of the present invention that during one 360 degree movement of a first one of the spools, the fixed length of cord is twisted in one rotational direction, and then during a subsequent 360 degree rotation of the other spool, the fixed cable is twisted in the opposite direction. This prevents continuous twisting of the fixed length of cable in one direction without the need for any form of complex electromechanical coupling between the fixed length of cable and the main length of cable supported on the spools. Thus, the fixed length of cable never continuously twists in one direction but rather alternately twists and untwists as the spools are rotated about their rotational axes.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limited the scope of the invention.